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arXiv 2024年

作者： Ponten, A. Sieber, H. Banto Oberhauser, B. Crivelli, P. Kirpichnikov, D. Gninenko, S.N. Hösgen, M. Molina Bueno, L. Mongillo, M. Zhevlakov, A. Uppsala University Department of Physics and Astronomy High Energy Physics Ångströmlaboratoriet Lägerhyddsvägen 1 Uppsala752 36 Sweden ETH Zürich Institute for Particle Physics and Astrophysics ZürichCH-8093 Switzerland Institute for Nuclear Research The Russian Academy of Sciences Moscow117312 Russia Center for Theoretical and Experimental Particle Physics Facultad de Ciencias Exactas Universidad Andres Bello Fernandez Concha 700 Santiago Chile Universität Bonn Helmholtz-Institut für Strahlen-und Kernphysik Bonn53115 Germany Carrer del Catedratic Jose Beltran Martinez 2 Paterna Valencia46980 Spain Bogoliubov Laboratory of Theoretical Physics JINR Dubna141980 Russia Matrosov Institute for System Dynamics and Control Theory SB RAS Lermontov str. 134 Irkutsk664033 Russia

In this study, we demonstrate the potential of the NA64 experiment at CERN SPS to search for New Physics processes involving e → μ transitions after the collision of 100 GeV electrons with target nuclei. A new Dark Sector leptonic portal in which a scalar boson φ could be produced in the lepton-flavor-changing bremsstrahlung-like reaction, eN → μNφ, is used as benchmark process. In this work, we develop a realistic Monte Carlo simulation of the NA64 experimental setup implementing the differential and total production cross-section computed at exact tree-level and applying the Weiszäcker-Williams phase space approximation. Using this framework, we investigate the main background sources and calculate the expected sensitivity of the experiment. The results indicate that with minor setup optimization, NA64 can probe a large fraction of the available parameter space compatible with the muon g−2 anomaly and the Dark Matter relic predictions in the context of a new Dark Sector leptonic portal with 1011 EOT. This result paves the way to the exploration of lepton-flavour-changing transitions in NA64. © 2024, CC BY.

关键词： Monte Carlo methods

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On Nonconvex Optimization Problems with D.C. Equality and Inequality Constraints

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IFAC-PapersOnLine 2018年第32期51卷 895-900页

作者： Strekalovsky, Alexander S. Matrosov Institute for System Dynamics and Control Theory of Siberian Branch of Russian Academy of Sciences Irkutsk664033 Russia

The paper addresses the nonconvex nonsmooth optimization problem with the cost function and equality and inequality constraints given by d.c. functions. The original problem is reduced to a problem without constraints with the help of the exact penalization theory. After that, the penalized problem is represented as a d.c. minimization problem without constraints, for which the new mathematical tools under the form of global optimality conditions (GOCs) are developed. The GOCs reduce the nonconvex problem in question to a family of convex (linearized with respect to the basic nonconvexities) problems. In addition, the GOCs are related to some nonsmooth form of the KKT-theorem for the original problem. On the base of the developed theory we propose new numerical methods for local and global search. © 2018

关键词： Constraint theory Cost functions Linearization Numerical methods Optimization equality exact penalty Global optimality conditions Inequality constraint Kkt points linearized problem local serarch

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Subject-oriented computing environment for solving large-scale problems of energy security research 5

Subject-oriented computing environment for solving large-sca...

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5th International Conference on Information Technology and Nanotechnology, ITNT 2019

作者： Bychkov, I.V. Oparin, G.A. Feoktistov, A.G. Sidorov, I.A. Gorsky, S.A. Kostromin, R.O. Edelev, A.V. Matrosov Institute for System Dynamics and Control Theory SB RAS Lermontov Street 134 Irkutsk664033 Russia Melentiev Energy Systems Institute SB RA Lermontov Street 130 Irkutsk664033 Russia

We represent a new approach to the development and use of a subject-oriented heterogeneous distributed computing environment for solving large-scale problems of energy security research. Both the development of scalable applications (distributed applied software packages) and the computing resources integration are conducted using the Orlando Tools framework. It supports the collaborative application development based on the continuous integration of their software. Computation management tools in Orlando Tools are integrated with a multi-agent system. We propose special multi-agent tools for the heterogeneous resource allocation in the environment. These tools apply knowledge about the subject domain specifics of solved-problems and computing environment characteristics. The effectiveness of such management is highlighted by the results of solving practical problems of energy security research. © 2019 IOP Publishing Ltd. All rights reserved.

关键词： Energy security

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On a solution to a nonlinear heat transfer model by the BEM

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AIP Conference Proceedings 2023年第1期2624卷

作者： A. L. Kazakov L. F. Spevak Matrosov Institute for System Dynamics and Control Theory Siberian Branch of the Russian Academy of Sciences Irkutsk Russia Irkutsk State Transport University Irkutsk Russia Ural State University of Railway Transport Ekaterinburg Russia Institute of Engineering Science Ural Branch of the Russian Academy of Sciences Ekaterinburg Russia

The paper deals with a nonlinear heat transfer model based on the nonlinear second order degenerate parabolic equation with arbitrary form of nonlinearity. Boundary value problems with two non-stationary boundary conditions are discussed: the problem with a specified heat wave front and the problem with a condition specifying the desired function at some manifold. A new existence theorem is formulated. Time-step algorithms based on the boundary element method and the dual reciprocity method are developed. Iteration procedures converging to the continuous solution on each time step are proposed. The algorithms are verified by comparison with known exact solution.

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Services for analysing series of satellite images for estimating the change dynamics of objects

Services for analysing series of satellite images for estima...

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2019 All-Russian Conference "Spatial Data Processing for Monitoring of Natural and Anthropogenic Processes", SDM 2019

作者： Fedorov, Roman K. Rugnikov, Gennadiy M. Avramenko, Yuriy V. Institute for System Dynamics and Control Theory of Siberian Branch of Russian Academy of Sciences Irkutsk Russia Irkutsk scientific center of Siberian Branch of Russian Academy of Sciences Irkutsk Russia Irkutsk state university Irkutsk Russia

To improve the efficiency of the use of remote sensing data in the tasks of managing territorial development, utility services have been implemented that allow us to catalog and simplify the use of methods for analysing remote sensing data as services. Services using reference vector techniques and neural networks of common Unet, FPN, Linknet and PSPNet architectures have been developed. Utility services allow for the regular and automatic processing of remote sensing data, including using scripts that link services and form a single processing process. Copyright © 2019 for this paper by its authors. Use permitted under Creative Commons License Attribution 4.0 International (CC BY 4.0).

关键词： Remote sensing

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Combined non-convex optimization algorithms based on differential evolution, harmony search, firefly, and L-BFGS methods

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IOP Conference Series: Materials Science and Engineering 2021年第1期1047卷

作者： P Sorokovikov A Gornov Matrosov Institute for System Dynamics and Control Theory of SB RAS 134 Lermontov Street Irkutsk 664033 Russian Federation

The paper presents an approach to the numerical investigation of the problems of finding a global optimum of multiextremal functions, based on the use of bioinspired and local search methods. Three combined non-convex optimization algorithms are proposed and implemented. As globalized bioinspired methods, differential evolution, harmony search, and firefly methods are used. For local descents, we used the L-BFGS method. The numerical study of modifications of the implemented approach has been carried out using known non-convex test functions. The developed algorithms have been applied to investigate the problem of the optimal orientation of the aircraft in space. The obtained numerical results allowed us to demonstrate the efficiency of the proposed algorithms.

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Rough Paths theory and Impulsive control: A Promising Connection

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IFAC-PapersOnLine 2018年第32期51卷 615-618页

作者： Samsonyuk, Olga N. Staritsyn, Maxim V. Matrosov Institute for System Dynamics and Control Theory of Siberian Branch of the Russian Academy of Sciences Irkutsk Russia

This short discussion note is devoted to establishing some connections between the framework of dynamical systems driven by signals of a low regularity (rough differential equations) and the mathematical theory of impulsive control (measure-driven systems), which, as we believe, would essentially enrich one another. More precisely, we attempt to elaborate an impulsive (discontinuous) extension of the theory of rough differential equation for input-affine models with states of unbounded first variation. In the paper, we are focused on a concept of solution for impulsive rough differential equations with vector-valued controls of bounded p-variation, p£ (1,2), and its constructive representation through a (discrete-continuous) Young's integral equation. © 2018

关键词： Integral equations Differential equations Dynamical systems Constructive representation Driven system Impulsive controls Input affine Mathematical theory Rough differential equations Rough paths Vector valued

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Test of vector portal with dark fermions in the charge-exchange reactions in the NA64 experiment at CERN SPS

arXiv

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arXiv 2023年

作者： Gninenko, Sergei N. Kirpichnikov, Dmitry V. Kuleshov, Sergey Lyubovitskij, Valery E. Zhevlakov, Alexey S. Institute for Nuclear Research The Russian Academy of Sciences Moscow117312 Russia of ANID Fernández Concha 700 Santiago Chile Center for Theoretical and Experimental Particle Physics Facultad de Ciencias Exactas Universidad Andres Bello Fernandez Concha 700 Santiago Chile Departamento de Física y Centro Científico Tecnológico de Valparaíso-CCTVal Universidad Técnica Federico Santa María Casilla 110-V Valparaíso Chile Bogoliubov Laboratory of Theoretical Physics JINR Dubna141980 Russia Matrosov Institute for System Dynamics and Control Theory SB RAS Lermontov str. 134 Irkutsk664033 Russia

We consider an experiment to search for dark sector particles in dark photon kinetic mixing model by analyze invisible and semi-invisible decays of neutral mesons M0 = π0, η, η′, ω, f2(1270), produced in the NA64 experiment at the CERN SPS. The approach proposed in Ref. [1] is to use the charge-exchange reactions π− + (A, Z) → M0 + (A, Z − 1);M0 → invisible or semi-invisible of high-energy pions (or kaons) at a nuclei target as a source of M0s, which subsequently decay invisibly into dark sector. This reaction chain would lead to a striking signature of the signal event - the complete disappearance of the beam energy in the setup. Using data obtained from the study of charge-exchange reactions at IHEP (Protvino) and Fermilab (Batavia) we show that the integral cross sections σ for production of the neutral mesons M0 are slightly deviate from phenomenological formula σ ∼ Z2/3, where Z is the nuclei charge. In particular, we present the formulas for the differential and integral sections that explicitly depend on the Mandelstam and Z variables. Derived formulas are used to predict the cross sections as a function of beam energy for several target nuclei, and to estimate the projection sensitivity for the proposed search for the M0 → semi-invisible and M0 → invisible decays through the vector portal to dark sector. Sensitivity to different semi-invisible decay modes of neutral pseudoscalar mesons is studied. © 2023, CC0.

关键词： Hadrons

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Minimum time function of a non-autonomous control system

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IFAC-PapersOnLine 2018年第32期51卷 704-707页

作者： Pogodaev, Nikolay I. Voronov, Vsevolod A. Matrosov Institute for System Dynamics and Control Theory of Siberian Branch of the Russian Academy of Sciences Irkutsk Russia

For a time-dependent control system we consider a “reversed” minimum time problem, which consists in finding the minimum time needed by the system, whose state is initially located in a given set, to reach a given point. We show that the minimum time function constructed in this way is a unique viscosity solution of a static first order PDE, provided that, at every point of the extended phase space, admissible velocities form a convex set containing zero in the interior. We also describe a version of the Fast Marching Method (FMM) that effectively solves this PDE. © 2018

关键词： control systems Phase space methods Set theory Fast marching methods First order Minimum time Minimum time problems Non autonomous system Nonautonomous Time dependent Viscosity solutions

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Test of the vector portal with dark fermions in the charge-exchange reactions in the NA64 experiment at CERN SPS

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Physical Review D 2024年第7期109卷 075021-075021页

作者： Sergei N. Gninenko Dmitry V. Kirpichnikov Sergey Kuleshov Valery E. Lyubovitskij Alexey S. Zhevlakov Institute for Nuclear Research of the Russian Academy of Sciences 117312 Moscow Russia Millennium Institute for Subatomic Physics at the High-Energy Frontier (SAPHIR) of ANID Fernández Concha 700 Santiago Chile Center for Theoretical and Experimental Particle Physics Facultad de Ciencias Exactas Universidad Andres Bello Fernandez Concha 700 Santiago Chile Institut für Theoretische Physik Universität Tübingen Kepler Center for Astro and Particle Physics Auf der Morgenstelle 14 D-72076 Tübingen Germany Departamento de Física y Centro Científico Tecnológico de Valparaíso-CCTVal Universidad Técnica Federico Santa María Casilla 110-V Valparaíso Chile Bogoliubov Laboratory of Theoretical Physics JINR 141980 Dubna Russia Matrosov Institute for System Dynamics and Control Theory SB RAS Lermontov str. 134 664033 Irkutsk Russia

We consider an experiment to search for dark sector particles in invisible (or semi-invisible) decays of neutral mesons M0=π0, η, η′, ω, f2(1270), which produced the charge-exchange reactions π−+(A,Z)→M0+(A,Z−1);M0→ invisible of high-energy pions (or kaons) on a nuclei target in the NA64 experiment at the CERN SPS. This reaction chain would lead to a striking signature of the signal event—the complete disappearance of the beam energy in the setup [Phys. Rev. D 91, 015004 (2015)]. Using data obtained from the measurements at IHEP (Protvino) and Fermilab (Batavia) we show that the integral cross sections σ for the production of the M0 s slightly deviate from the phenomenological formula σ∼Z2/3, where Z is the nuclei charge. In particular, we present the formulas for the differential and integral cross sections that explicitly depend on the Mandelstam and Z variables. Derived formulas are used to predict the M0 yield as a function of beam energy for several target nuclei, and to estimate the projection sensitivity for the proposed search in the dark vector portal model. Sensitivity to different decay modes of M0s is explored.

关键词： Particle dark matter Hypothetical gauge bosons

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